Thermoplastic Sealing Ring Backup for Long-Term Wellbore Sealing

Solution Overview

Problem

Elastomeric seals used in wellbore operations suffer from reduced sealing capacity over time due to stress relaxation, thermal aging, and permanent dimensional changes, especially at elevated temperatures, leading to potential failures and leaks.

Innovation Solution

A sealing system design featuring a thermoplastic sealing ring with a secondary seal on the inside or outside diameter, which is energized to rotate and create a chamfer, increasing contact stress at both primary and secondary seal locations, thereby enhancing sealing force and reducing the impact of thermal cycling and pressure differentials.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If elastomeric seals are used in wellbore operations at elevated temperatures, then initial sealing capacity is achieved, but sealing capacity deteriorates over time due to stress relaxation, thermal aging, and permanent dimensional changes

Engineering Contradiction:

Improvesealing capacityVSAvoidservice life

Core Design Contradiction:

ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The patent changes the material parameter from elastomeric to thermoplastic polymer, which maintains dimensional stability and sealing force under elevated temperatures and prolonged service conditions, preventing the degradation issues associated with elastomeric materials

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent employs a composite sealing system combining thermoplastic polymer material with specific geometric features (chamfered surfaces, secondary seals) to create a sealing structure that resists thermal aging and stress relaxation while maintaining long-term sealing capacity

Inventive Principle:

Principle #40Composite materials

2Reliability

If pressure differentials are applied across a seal to contain hydrocarbons, then sealing function is achieved, but seal failure is induced due to substantial pressure differentials

Engineering Contradiction:

Improvesealing functionVSAvoidpressure differential

Core Design Contradiction:

ReliabilityVSStress or pressure

Solution Approach 1:

The patent applies local quality by creating chamfered surfaces at specific locations where seals contact the thermoplastic material, concentrating sealing force at these localized regions to withstand high pressure differentials without causing overall seal failure

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent segments the sealing system into multiple components including primary seals, secondary seals, and chamfered surfaces, distributing the pressure differential load across multiple sealing interfaces rather than relying on a single seal

Inventive Principle:

Principle #1Segmentation

3Reliability

If seals are expanded to create sealing contact, then sealing capacity is improved, but deformation and internal stress on sealing elements increase leading to failure

Engineering Contradiction:

Improvesealing capacityVSAvoidsealing element integrity

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent inverts the traditional sealing approach by using a rigid thermoplastic material that maintains its shape rather than relying on elastomeric material expansion, eliminating the deformation and internal stress issues associated with expanding seals

Inventive Principle:

Principle #13The other way round (Inversion)

4Adaptability or versatility

If elastomeric seals are subjected to thermal cycling between elevated and sub-ambient temperatures, then operational flexibility is achieved, but sealing force is lost due to thermal aging and permanent dimensional changes

Engineering Contradiction:

Improvetemperature range operationVSAvoidsealing force

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent changes the material parameter from elastomeric to thermoplastic polymer, which maintains dimensional stability and sealing force under elevated temperatures and prolonged service conditions, preventing the degradation issues associated with elastomeric materials during thermal cycling

Inventive Principle:

Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The design significantly increases the service life of elastomeric sealing materials, improves low-temperature performance, and reduces the risk of seal failure by maintaining contact stress at both sealing surfaces, even under high hydrostatic pressures.

Implementation Method 1

A sealing system design featuring a thermoplastic sealing ring with a secondary seal on the inside or outside diameter, which is energized to rotate and create a chamfer, increasing contact stress at both primary and secondary seal locations

Methodology Applied

Scientific EffectPressure: Pressure Increase

Data Source

PatentUS20230407972A1Deployable pressure energized sealing backup systems for improved long term reliability

Publication Date: 2023.12.21 HALLIBURTON ENERGY SERVICES INC

AI summary

Provided is a sealing ring and a sealing system. The sealing ring, in one aspect, includes a sealing ring member having an inside diameter face, an outside diameter face, a primary seal side face, and a gland side face. The sealing ring according to this aspect further includes a secondary seal coupled to at least one of the inside diameter face, the outside diameter face, the primary seal side face or the gland side face.